The present invention relates to transmission apparatus. More particularly, the present invention relates to hydraulic apparatus having input blades and output blades that introduce and remove energy to a fluid.
Typically, transmission apparatus are provided between a power source and a work unit. Power sources typically convert one type of energy into mechanical energy. For example, an internal combustion engine coverts the energy stored in hydrocarbon fuel to rotational energy. Work units typically use this mechanical energy to perform a useful function. For example, the tires of a vehicle use the rotational energy provided by the engine to propel the remainder of the vehicle.
The transmission apparatus is positioned between the power source and the work unit to convert the output of the power source into a more useable form for the work unit. For example, a vehicle transmission apparatus converts the relatively high rpm and low torque output of an internal combustion engine into a relatively low rpm and high torque input to the tires of a vehicle. This permits the tires to accelerate the vehicle relatively quickly from rest without overloading the available output torque of the engine. Furthermore, this enables coordination of the speed and torque output of the engine with the speed and torque requirements of the tires.
According to the present invention, a transmission apparatus is provided that is configured to transmit energy from a power source to a work unit. The transmission apparatus includes an outer housing defining an interior region containing a fluid, an input shaft, an output shaft, first and second pumps, and first and second turbines.
The input shaft is configured to rotate about a first axis of rotation and is coupled to the power source to receive energy therefrom. The output shaft is configured to rotate about a second axis of rotation and is coupled to the work unit to transmit energy thereto.
The first pump is positioned in the interior region of the outer housing and coupled to rotate with the input shaft to input a first portion of the energy from the power source into the fluid contained in the interior region of the outer housing. The first turbine is positioned in the interior region of the outer housing to receive energy from the fluid contained in the interior region of the outer housing and to transmit said received energy to the output shaft.
The second pump is positioned in the interior region of the outer housing in a position spaced apart from the first pump and coupled to rotate with the input shaft to input a second portion of the energy from the power source into the fluid contained in the interior region of the outer housing. The first turbine is positioned between the first and second pumps.
The second turbine is positioned in the interior region of the outer housing in a position spaced apart from the first turbine to receive energy from the fluid contained in the interior region of the outer housing and to transmit said received energy to the output shaft. The second pump is positioned between the first and second turbines.
According to alternative embodiments of the present invention, each pump includes a set of pump blades and each turbine includes a set of turbine blades. Each set of pump blades is axially spaced apart and each set of turbine blades is axially spaced apart.
According to other alternative embodiments of the present invention, a transmission apparatus is provided that is configured to receive energy from a power source and to transmit a portion of said energy to a work unit. The transmission apparatus includes a first shaft configured to receive power from the power source, a second shaft configured to transmit energy to the work unit, means for adding energy from the first shaft to a fluid to create a flow path, and means for removing energy from the fluid in the flow path. The adding means transfers energy received by the first shaft into the fluid at a first location in the flow path and at a second location in the flow path downstream of the first location in the flow path. The removing means transfers energy from the fluid in the flow path to the second shaft at a third location downstream of the first location and upstream of the second location and at a fourth location downstream of the second location.
According to the present invention, a method for transmitting energy from a power source to a work unit is provided. The method includes the step of providing an input shaft configured to receive power from the power source, a housing having an interior region containing a fluid, and an output shaft configured to transmit power to the work unit. The method further includes the steps of adding energy from the input shaft to the fluid to create a flow path, said addition of energy occurring at a first location in the flow path: removing energy from the fluid at a second location in the flow path downstream of the first location in the flow path: transferring said energy removed from the second location in the flow path to the output shaft; adding energy from the input shaft to the fluid at a third location in the flow path downstream of the second location in the flow path; removing energy from the fluid at a fourth location in the flow path downstream of the third location in the flow path: and transferring said energy removed from the second location in the flow path to the output shaft.